# Quality Assurance

> Petroleum products are bought and sold against a specification. Yorkwell Petroleum checks the evidence for that specification before a trade proceeds.

URL: https://yorkwellpetroleum.com/quality-assurance/

## What we check

- The specification named in the contract
- Certificates of quality and quantity
- Inspection and laboratory reports
- That the documents agree with each other and with the contract

## From specification to acceptance

1. **Specification**: Named in the contract
2. **Sampling**: Taken by the inspector at the tank or vessel
3. **Laboratory test**: Against the methods in the standard
4. **Certificate of quality**: Issued by the laboratory
5. **Comparison**: Results checked against the contract
6. **Acceptance**: Or the remedy the contract provides

Samples are usually retained so that a result can be re-tested if it is disputed.

## Common product standards

| Product | Standard commonly named |
| --- | --- |
| Diesel | EN 590 |
| Jet fuel | ASTM D1655 or DEF STAN 91-091 |
| Gasoline | EN 228 or ASTM D4814 |
| Marine fuels | ISO 8217 |
| LPG | ASTM D1835 or EN 589 |
| Crude oil | Assay for the grade and origin |

## Independent inspection

Where a contract calls for it, we coordinate inspection by an independent inspection company at the loading or discharge point. The inspector's report, and not our opinion, is the evidence the parties rely on.

We keep the quality documents for each trade so that the parties can refer back to them. The specification for each product is listed on our [trading](https://yorkwellpetroleum.com/energy-commodity-trading/) page.

## Questions we are asked

### Who appoints the inspector?

The contract names the inspector or says how one is chosen. Inspection companies are independent of buyer and seller.

### What happens if a result is outside the specification?

The contract sets out the remedy. Common ones are re-testing of retained samples, a price adjustment or rejection.

### Which documents show quality and quantity?

A certificate of quality from the laboratory and a certificate of quantity from the inspector.

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Yorkwell Petroleum · 440 Louisiana St, Ste 900, Houston, TX 77002 · info@yorkwellpetroleum.com · +1 (713) 239-3396